Where should reactions involving the evolution of toxic gases be performed?

Experiments involving the evolution of any kind of the harmful gases, lest of all toxic, should never be performed in an open environment. Such reactions involving the toxic gas evolution should be performed in a secured environment, such as the fume hood. This will prevent the toxic gases released from escaping and getting inhaled by the person conducting the experiment.  

i'll try what topic lol

where in your body is there an enzyme that does function at a high or low ph? what is the name of that enzyme and its function?